CHELONUS. 395 



second cubital cellule contracted at the apex ; at the base the nervures are white, at the 

 apex fuscous, the stigma being also fuscous. 



3. Chelonus sonorensis. (Tab. XVI. fig. 4, $ .) 



Niger, geniculis, tibiis tarsisque albidis, apioe tibiarum posticarum nigro ; tborace punctulato; alis fumatis, 



basi hyalinis. $ . 

 Long. 5 millim. 



Hab. Mexico, Northern Sonora (Morrison). 



Antennae a little longer than the body; the flagellum almost bare, the scape covered with 

 rather long pale hair. Head covered with a sericeous pile, in front strongly transversely, 

 at the sides behind the eyes longitudinally, striated ; clypeus shining, obscurely punc- 

 tured ; tips of the mandibles piceous. Thorax covered with a close sericeous pile, 

 especially on the sides; coarsely rugose, with some short stout longitudinal keels in 

 front of the scutellum, the latter shining, impunctate ; metanotum coarsely reticulated, 

 with two stout keels in the centre, its apex semiperpendicular, bordered above by a 

 stout keel, and ending in a blunt tooth at the sides. Abdomen somewhat pyriform, a 

 little longer than the head and thorax united, becoming gradually and slightly broader 

 to the apical fourth ; covered with a short dense sericeous pile, which is still denser 

 towards the apex ; longitudinally rugosely reticulated, more strongly so at the base ; 

 with two stout curved keels and two elongated yellowish-white marks at the base ; the 

 ventral surface at the base also yellowish-white. Legs testaceous-white ; the coxse, tro- 

 chanters, basal three fourths of the four anterior femora, the posterior femora entirely, 

 the tips of all the tarsi, and the apices of the hind tibiae, black ; the tips of the joints of 

 the hind tarsi fuscous. Wings hyaline, darker in front of and (especially) below the 

 stigma ; the costa and nervures behind the stigma yellowish-white, the nervures in front 

 of it fuscous, the stigma itself black ; a curved thin white cloud in the first cubital 

 cellule ; the basal nervure dilated at the apex, curved near the costa ; the radial nervure 

 curved at the base and forming a rounded angle where the second transverse cubital 

 nervure is received ; the cubital nervure curved downwards to the end of the second 

 cubital cellule, and then running obliquely and straight to the apex, the apical part 

 being much fainter than the basal ; the first cubital nervure oblique, straight. 



a t> 



4. Chelonus annulipes. 



Niger, pedibus anterioribus pro parte annuloque tibiarum posticarum albis ; tborace rugoso ; alis fumatis, basi 



fere byalinis. 

 Long, fere 5 millim. 



Eab. Guatemala, Volcan de Atitlan 3500 feet (Champion) ; Panama, Bugaba 

 (Champion). 



Antennse 24-jointed, microscopically pilose, the scape reddish. Head covered with 

 glistening white hair; rugose, but not so strongly so on the top; front depressed. 



3ee2 



